Safety device for shell-fuses.



H. MOREN. SAFETY DEVICE FOR SHELL FUSES. APPLICATION FILED APR 8 1915Patented Nov. 21, 1916.

UNITED STATES PATENT orrron.

OR TO AKTIEBOLAGET BOFORS-GULLSPANG, A COMPANY LIMITED.

SAFETY DEVICE FOR SHELL-FUSES.

Specification of Letters Patent.

Patented Nov. 21, 1916.

Application filed April 8, 1915. Serial No. 19,877.

To all whom it may concern:

Be it known that I, HUeo Money, a subject of the King of Sweden,residing at Bofors, Sweden, have invented new and useful Improvements inSafety Devices for Shell-Fuses, of which the following is aspecification.

The present invention relates to a shell fusewhich is simple and cheapin manufacture and which, in safe condition, provides absolute safety inthe case of an accidental ignition of the primary or secondary ignitingcharge, the latter being, as known, sensitive to some extent to exteriorinfluence and sufficiently powerful to necessitate special steps ofcaution, for instance inclosing it, in the safe condition, in anexpansion chamber the walls of which are internally lined with a sleeveof suitable material for resisting an explosion of the secondaryigniting chz-irge in this position. In these fuses, in the safecondition, the detonator and the detonator charge are kept separated bya member which, on firing the gun, obtains a relative rearward movementby reason of its inertia and thereby compresses a return member,generally a coiled spring, which, as soon as the projectile has left themuzzle of the gun, resumes its original shape and returns the separatingmember, which latter simultaneously moves the detonator anddetonatorcharge together by means of an elastic locking device, so thatan explosion of the detonator may be communicated to the detonatorcharge. According to the present invention such an arrangement is madethat the sleeve internally lining the \illlS of the expansion chambereither in itself constitutes the member which carries the detonator inactive position with relation to the detonating charg or vice versa, orthe said sleeve is directly connected to said actuating member, thelining sleeve or liner then being made so much shorter than thesurrounding chamber as to be sufficiently reciprocatable for the action.

In the accompanying drawing Figure 1 shows a form of the invention,adapted to point fuses, such a fuse being shown in a longitudinalsection in safe condition; Fig.

2 shows a view corresponding to Fig. 1 in active condition. Fig. 3 showsa longitudinal section of a base fuse embodying the invention in safecondition and Fig. 1 a correspondlng view in active condltion.

In the form shown m Figs. 1 and 2, the

is provided with an axial tire channel 9 com- 7 g with the axlal firechannel 10 in the fuse body 1, leading to the charge 11 of the detonatorsleeve. On the rear end of the body 1 a sleeve shaped portion 12 isscrewed, while the detonator sleeve 13 is screwed into said body. Insidetheportion 12. the liner 1+ is movable. This liner is made resilient inboth ends by slits of which only those in the forward end areillustrated in the Figs. 1 and 2., the slits in the rear end beingsituated in another plane. These slits have for their purpose to makethe sleeve resilient. In Fig. 1 it is at rest against the body 1 andsurrounded by the return spring 1:") which rests, at its front end,against the flange 16 and at its rear end against the shoulder 17 on thefuse portion 12. Inside the rear end of the. latter, the sleeve 19containing the detonating charge 18 is situated, resting at the rearagainst the bottom 20 of the fuse body and being kept from forwardmotion by the rear, contracted end of the sleeve 14. In the frontclosure 21 of the sleeve 19, a hole is provided for the passage of thedetonator sleeve 13, and behind this hole there is a recess 22 in thecharge 18 for receiving the detonator sleeve 13.

In Fig. 2 which shows the position of the same parts after theprojectile has left the muzzle of the gun, the primary activatingmembers 7 and 8 have first liberated the hammer G in a known manner, sothat ignition can occur on impact, but moreover the sleeve or liner 11,which has been retracted at the initial shock and squeezed around thesleeve 19 with its rear, contracted end which is somewhat resilient, hascarried forth said sleeve 19 when returned by the spring 15 to itsoriginal position. The sleeve l i thus forms an activating device forthe secondary members of the fuse, so as to move, when the gun is fired,the detonator and detonator charge into operative mutual position.Instead of being resilient in its rear portion and thus serving initself as an activating member. the sleeve of course may be combinedwith a particular resilient member of municating at its rear-end suchnature as to squeeze the detonator to v with the ignition point 32 andthe fire chan- I nels 33 and containing a powder charge 34.

.latter.

From this bore 30, a fire channel 35 leads forward to the charge 36 ofthe detonator sleeve. The fuse body 23 has two front bores 37 and 3S,separated by a partition wall 39. The bore 37 is closed by the cover 40and contains the detonating charge 41 which has a recess 42 fitting thedetonator sleeve 43. The partition wall 39 has a perforation suitablefor the passage of sleeve 43. Inside the bore 38. resting against thepartition wall 39, is the movable sleeve 4 V which is firmly secured tothe resilient member 45. Said member retains the detonator sleeve 43 inthe position shown by engaging the slot 4L6. A return spring 47 restswith one end against the rear wall of the bore 38 and with the otheragainst the resilient member and-surrounds the detonator sleeve 43. Therear end of the latter rests against the partition between the bores 30and 38. From this partition a stud 48 pro jects, which is traversed bythe above mentioned fire channel 35, and which engages a hole in thecover- 49 of the detonator sleeve 43 and serves as a guide for the InFig. 4, which shows the same form of the fuse after the projectile hasleft the muzzle-of the gun, the activating members 28 and 29 havereleased the hammer 27 while the sleeve or liner 4% has been returned toits forward position by the spring 47 together with the detonator sleevewhich is engaged by means of the resilient member 45. This member th'ushere is the secondary activating member.

If in the position of the members shown in Figs. 1 or 3, the charge 11(or 36) of the detonator sleeve 13 (or 43) would explode either by anexplosion of the ignition cap or for some other reason, the liner 14 (or44) which is destroyed itself, will prevent the bursting of thesurrounding fuse body and thus the ignition of the surrounding shellcharge. The bottom of the detonator sleeve which is flattened by theexplosion sticks in the hole in the partition wall 39 and therebyprevents the ignition of the bursting charge 18 or 41.

' The use of a liner in the explosion chamber enables a softer and moreeasily worked material to be used in the fuse body proper.

Having now particularly described the nature of my invention and themanner of its operation, what I claim is:

l. A safety device for fuses consisting of a movable liner for the wallsof the expansion chamber of the fuse having such a length that itsurrounds the detonator in' safe condition along the entire length ofsame and protects the walls of the expansion chamber in case of anunintentional detonation of the detonator, said liner at the same timeserving as an actuating member.

2. A safety device for fuses consisting of a movable liner for the wallsof the expan sion chamber of the fuse having such a length that itsurrounds the detonator in safe condition along the entire length ofsame and protects the walls of the expansion chamber in case of anunintentional detonation of the detonator, said liner being resilient atone end.

3. A safety device for fuses, consisting of a movable liner for thewalls of the expansion chamber of the fuse having such a length that itsurrounds the detonator in safe condition along the entire length ofsame and protects the walls of the expansion chamber in case of anunintentional detonation of the detonator, and a resilient member towhich said liner is connected, sald resilient member being adapted tograsp the detonator and carry it forth with the liner.

4. A safety device for fuses, consisting of a movable liner for thewalls of the expan sion chamber of the fuse having such a length that itsurrounds the detonator in safe condition along the entire length ofsame and protects the Walls of the expansion chamber in case of anunintentional detonation of the detonator, and a resilient member,connected to said liner and adapted to grasp the detonator charge andcarry it forth with the liner.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

- HUGO MOREN.

Witnesses KAN EISMAN,

ERIK Fnonn'r'r.

